Mgen Test: Mycoplasma genitalium plus full STI screen
$39no additional costs — see fees page
$39 SMS pathology referral for Mycoplasma genitalium (Mgen) testing as part of the full STI screen. Walk into any Australian pathology lab. Most results within 24 hours.
If anything comes back positive, your follow-up telehealth consult with a Specialist GP is included at no additional cost.
5,000+ collection centres across Australia (any major pathology lab)
All states, regional and remote — no appointment
Includes resistance testing — if positive, see Mgen treatment for the next step
You will receive a pathology referral by SMS. Take it to any pathology clinic.
Everything you need to know about Mgen testing in Australia
What this page covers. Mycoplasma genitalium (often called "Mgen" or "MG") is a bacterial sexually transmitted infection that has only been recognised as a clinically important cause of infection in the past 20 years. It is now tested routinely as part of comprehensive STI screening in Australia, particularly for people with persistent symptoms after standard treatment for chlamydia or gonorrhoea. This page covers what an Mgen test involves, what a resistance test add-on means in practice, when the test is reliable after exposure, and what positive and negative results actually mean.
What Mgen is. Mycoplasma genitalium is a very small bacterium that lives in the genital and urinary tract. It causes urethritis in men (inflammation of the urethra, often presenting as discharge or burning urination) and cervicitis in women (inflammation of the cervix). Many people with Mgen have no symptoms at all. Untreated infection in women can cause pelvic inflammatory disease and may contribute to infertility, though the evidence is less established than for chlamydia. Mgen is particularly relevant for people whose symptoms persisted after treatment for chlamydia or gonorrhoea, because Mgen often co-occurs and is not cleared by the antibiotics used for those infections.
The test itself. The standard Mgen test is a nucleic acid amplification test (NAAT) on a urine sample (men) or self-collected vaginal swab (women). The lab detects the genetic material of Mycoplasma genitalium. Many Australian labs now run an Mgen test that also includes a resistance assay — this checks for specific mutations in the bacterium that make it resistant to the standard treatment regimen. The resistance result is reported alongside the positive result and guides which regimen the Specialist GP recommends.
Why a resistance test matters. Mgen has high rates of resistance to the standard treatment regimen used in Australia. Around half of Mgen isolates carry a resistance mutation, and treating with a resistant regimen leaves the infection in place. Knowing the resistance status before treatment lets the Specialist GP match the regimen to your specific infection, which has significantly higher cure rates than treating blindly. Not all labs run the resistance assay automatically, so the Specialist GP can specifically request it on the pathology referral when needed.
Time before a test is reliable. Mgen NAAT tests are reliable from about 2 weeks after the last possible exposure. Testing earlier is reasonable if symptoms are present, but for screening without symptoms, the 2-week wait is standard. See when to test after exposure for the full timing guide across all STIs.
Who should test. Current Australian guidelines recommend Mgen testing for: anyone with symptoms of urethritis or cervicitis (discharge, burning urination, pelvic pain), anyone whose symptoms persisted after standard treatment for chlamydia or gonorrhoea, sexual contacts of someone diagnosed with Mgen, and women being assessed for pelvic inflammatory disease. Routine Mgen screening for people without symptoms is not currently recommended — the infection is common enough that universal screening would lead to a lot of unnecessary antibiotic use. Mgen is sometimes added to comprehensive STI panels by request.
Why Mgen is not in every routine STI screen. The infection is common in the general population, often without symptoms, and the antibiotic regimens needed to clear it are increasingly limited because of resistance. Australian guidelines reserve testing for people with symptoms or specific exposure concerns to avoid driving further antibiotic resistance. This is different from chlamydia and gonorrhoea, where routine screening is recommended for sexually active people in higher-risk groups. If you specifically want Mgen included in your STI screen, mention this at the consult.
A positive result. The Specialist GP calls to discuss the result, the resistance status (if tested), and the regimen that applies. See Mgen treatment for the full clinical detail on the regimen options, what sequential combination treatment looks like, and follow-up testing. The conversation also covers partner notification for partners in the past 2 to 3 months.
Why Mgen results take longer than chlamydia and gonorrhoea results. The Mgen test itself runs at a similar speed to other NAAT tests, but if a resistance assay is added, the lab runs that as a separate step. Total turnaround is typically 3 to 5 business days, compared with 1 to 2 days for a standard chlamydia and gonorrhoea NAAT. Some labs only run Mgen testing on certain days of the week, which can add another day or two. The Specialist GP can advise what to expect from your specific pathology provider.
Mgen in women with pelvic inflammatory disease. When pelvic inflammatory disease is diagnosed and chlamydia and gonorrhoea tests are negative, Mgen is one of the infections worth testing for next. Mgen can cause PID and the treatment regimen is different from what would be used empirically for chlamydia or gonorrhoea PID. The Specialist GP can arrange both the test and any urgent in-person review needed for ongoing pelvic pain.
A negative result. A negative Mgen test taken at the right time (at least 2 weeks after the last possible exposure) reliably excludes infection. If your symptoms continue despite a negative test, the Specialist GP discusses other possible causes — trichomonas, persistent inflammation, prostatitis in men, or non-infectious causes of urethral symptoms.
Persistent symptoms after chlamydia or gonorrhoea treatment. One of the most common reasons to test specifically for Mgen is symptoms that did not clear after standard treatment for those infections. The classic situation: a man treated for non-specific urethritis with a 7-day course of tablets, whose urethral symptoms return or never fully cleared. Mgen is a major cause of this picture. The Specialist GP can arrange the Mgen test (with resistance assay) and discuss what the next regimen would be if positive.
Partner notification. Sexual partners from the past 2 to 3 months should be informed so they can test and be treated if positive. Mgen has the additional complication that resistance is inheritable across the sexual network — treating one partner without treating others can leave a reservoir of resistant Mgen circulating. The Specialist GP can help with the words for direct notification or anonymous services.
Antibiotic stewardship. Mgen sits at the centre of the antibiotic stewardship conversation in sexual health because the regimens needed to clear it are among the few options still reliably effective for a range of other infections. Treating Mgen well, including using the resistance test before treatment, helps preserve these regimens for the broader patient population. This is part of why routine screening of people without symptoms is not recommended — it would lead to treating many people whose infection might not have caused them harm, at the cost of further resistance.
Confidentiality. All Mgen testing is confidential. The consult and results stay between you and the Specialist GP. Mgen is not a notifiable infection in most Australian jurisdictions, so there is no public health reporting required.
Want to discuss your situation? A Specialist GP phone consult can discuss whether Mgen testing is appropriate for your situation, whether to include the resistance assay, what timing makes sense relative to any exposure, and what positive or negative results would mean. See the hero section above for booking. For Melbourne residents, see Mgen testing in Melbourne. For pathology collection across Australia, see pathology collection centres.
Frequently asked questions
Not sure what you have? Compare symptoms side by side in our STI Comparison Guide — plain English, no jargon.
Not sure when to test? See our When to Get an STI Test guide — how long after exposure to test, testing frequency, and what to do after exposure.
Mycoplasma genitalium (Mgen for short) is a sexually transmitted bacterium that was only confirmed as a cause of human infection in the 1980s and recognised as a clinically important cause of infection in the past two decades. Many people are unaware of it because it has not historically been part of routine STI screening in Australia. It causes urethritis in men and cervicitis in women, often with no symptoms, and is increasingly important to test for in people whose symptoms persisted after standard treatment for chlamydia or gonorrhoea.
Not usually. Australian guidelines reserve Mgen testing for people with symptoms (discharge, burning urination, pelvic pain), persistent symptoms after chlamydia or gonorrhoea treatment, sexual contacts of someone diagnosed with Mgen, or assessment for pelvic inflammatory disease. Routine screening of people without symptoms is not recommended because the infection is common, often does not cause harm, and treating large numbers of people would accelerate antibiotic resistance. The Specialist GP can discuss whether Mgen testing is appropriate for your specific situation.
Yes, this is one of the main reasons to test specifically for Mgen. Persistent urethral symptoms after standard chlamydia treatment is a classic presentation. The same antibiotic regimen that clears chlamydia does not reliably clear Mgen, so an Mgen co-infection that was not diagnosed at the start continues to cause symptoms. The Specialist GP can arrange the Mgen test (ideally with the resistance assay) and discuss what regimen would apply if it is positive.
The resistance assay is an add-on to the standard Mgen test that checks for specific genetic mutations in the bacterium that predict whether the standard treatment will work. About half of Mgen infections in Australia carry one of these mutations, and treating with the standard regimen when resistance is present leaves the infection in place. The Specialist GP usually requests the resistance assay alongside the Mgen test when testing for a positive contact or for persistent symptoms after standard treatment.
At least 2 weeks. Mgen NAAT tests are reliable from about 2 weeks after the last possible exposure. If you have current symptoms (discharge, burning urination), testing earlier is reasonable because symptomatic infections usually have higher bacterial loads. For testing after a known exposure to a partner with Mgen, the 2-week wait is the standard.
Repeat the test 2 weeks after your last sexual contact with them. A negative result early in the window can become positive once the infection has had time to develop. Unlike for some STIs, treating partners on the basis of a positive contact alone is not the standard approach for Mgen because of the resistance situation — a confirmed positive result with a resistance assay guides treatment more reliably. The Specialist GP can discuss what makes sense for your situation.
Typically 3 to 5 business days, including the resistance assay if added. This is longer than standard chlamydia and gonorrhoea results (1 to 2 days) because the resistance test runs as a separate lab step. Some labs only process Mgen tests on specific days of the week, which can add another day or two. Urgent results can sometimes be expedited through the Specialist GP if symptoms are severe or there is a clinical reason.
Pathology lab fees for Mgen testing have a Medicare item number that applies in specific situations — particularly for symptomatic presentations and for persistent symptoms after chlamydia or gonorrhoea treatment. The resistance assay add-on may have a separate fee depending on your pathology provider. People without Medicare have different fee arrangements. See our fees page for Clinic365 fees, and the Specialist GP can confirm the pathology fee structure at booking.
For men, the first-part urine sample is the standard test for Mgen — the same sample used for chlamydia and gonorrhoea testing. Hold the urine for at least an hour before collecting. For women, a self-collected vaginal swab is more sensitive than urine for Mgen. The Specialist GP discusses which sample makes sense at the consult, and the same referral can usually cover chlamydia, gonorrhoea, and Mgen at one sample.
Not by default. Pathology results go to the ordering clinician (the Specialist GP at Clinic365) rather than your regular GP. If you would like a summary sent to your regular GP, mention this at the consult and we can arrange that with your consent. Mgen is not a notifiable infection in most Australian jurisdictions, so there is no public health reporting required.
